Grinding machine



Jan. 13, 1942. c, G. FLYGARE r-:rAL

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c. G. FLYGARE ETAL GRINDING MACHINE Filed Nov. 4, 1939 6 Sheets-Sheet 4 an 22d lll E F. 5 m

.Ja/1N Z Enns/DE Jan. 13, 1942. c. G. FLYGARE E1-AL 2,270,205

GRINDING MACHINE Filed Nov. '4, 1939 6 Sheets-Sheet 5 4' zo zaza? Zm 20a a 223 o3 Lava aan -l 75 asa n 22a a 4 f a 22s v o6 211 l 22e 5 ///Ll 3f-.

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` GRINDING MACHINE "Jan, 13, 1942..

Filed Nov. 4, 1939 6 Sheets-Sheet 6 MWL-Amm Patented Jan. 13, 1942 Carl G. Flygare, Worcester, and John I. Garside,

West Boylston, Mass., assignors to Norton Company, Worcester, Mass., a corporation of Massachusetts Application November 4, 193e, serial No. 302,796

12 claims. (Cl. 51-215) The invention relates to grinding 'machines and more particularly to a multiple wheel slide cylindrical type grinding machine in which the work to be ground is automatically loaded into the machine.

One object of the invention is to provide a simple, thoroughly practical cylindrical grinding machine in which work pieces are automatically loaded into and removed from the machine. Another obrject of the invention is to providean automatically controlled cylindrical grindingmachine *with a workloading device whereby a work i piece maybe mechanically conveyed from an endless conveyor into an operating position in the machine. f

A further object of the invention is to provide a hydraulically operated, manually controlled work conveyor mechanism to grip a work piece on a work conveyor adjacent to the machine andk in which the work driving mechanismis con-v trolled by .the insertion of awork piece into `the machine. A furtherobject is to provide a work driving mechanism which rotates a work drive pin slowly until it seats in `an operative position to rotate the work piece,after which the Work` piece is automatically speeded up to a normal grinding speed.

A further object of tnefinvention is to profl vide an automatic work loading and unloading mechanism which is arranged to convey 1inground work pieces from an operating position on a transversely movable vgrinding machine steadyrest and to place an unground work piece on said steadyrest as it moves transversely toward an operative position. -It is a further object of the invention to provide an electrical control mechanism forthe various mechanisms of themachine which are so arranged and intel'` locked that the various mechanisms function automatically in the desired sequence. l

A further object of the invention isto providey an automatically'actuated table locating or trave ersing mechanism whereby-the work supporting table is automatically adjusted longitudinally to position the work piece being groundin operative position with relation to the grinding wheel;

Other objects Will be inpart obvious or in part pointed out hereinafter.

The invention accordingly consists in the fea7 tures of construction, combinations of elements,

I and arrangements of parts, as will be exemplified inthestructure to be hereinafter described, and the scope of the application of which ywill be in` dicated in the followingclaims.

' Inythe accompanying drawings, in whichis shown one of various possible embodiments o the mechanical features of the invention,

` Fig.` 1 isV a front elevation of a grinding machine, showing the work loading mechanism;

Fig.I 2r is a diagrammatic view showing the hydraulic piping diagram and also the electrical Wiring diagram ofthe machine;

Fig. Sis a fragmentary elevationand diagram-` matic view, on `an enlarged scale, of the control lever and switch together with the solenoid valve for controlling the work transferring mechanism;

Fig. 4 is a fragmentary cross sectional view,` on anenlarged scale, taken approximately on the line 4-4 of Fig. 1, showing the motor driven table traversing mechanism? Fig. 5 is a fragmentary end elevation of the work steadyrest and its supportingv slides;

Fig. 6 is a fragmentary front elevationpon an enlarged scale, of 'the work steadying rest and work loading mechanism, as shown inFig. 1, having parts broken away andshown in section tomore clearly show the operating mechanisnu'v Fig. 7 is a cross sectional View, on an enlarged scale, taken approximately onthe line 'l--l of Fig. 6,'through the fluid vmotor for transversely moving the steadyrest unit; f

Fig. 8 is a fragmentary plan view, on an en-` larged scale,` of the work driving .and automatic table locating mechanism, having parts broken away and shown in section to more clearly show the operating construction;

Fig. 9 is a fragmentary plan View, -on an enlarged scale, of the steadyrest unit,'the footstock, and the automatic work loading mechamsm;

Fig. 10 'is a fragmentary sectional view, taken approximately on the line I--Ill of Fig. 9; and

.Fig. llis a fragmentary longitudinal sectional view, taken approximately on the line H--H of Fig. 10, showingthe guard plate which closes the open; side of the clip 221 during the transfer jofg;

gare No. 2,151,669, dated March 21, 1939, to which reference may be had for details of disclosure not contained herein.

A grinding machine has been illustrated, comprising a base I5 which supports a longitudinally movable work supporting table I6. The base I5 is provided with a flat Way I1 and a V-way IB which mate with correspondingly shaped ways on the table |6 to slidably support and guide the table I6 during its longitudinal movement thereon. The table |6 is provided with a rotatable work support which comprises a headstock 28 having a headstock center 2| and a footstock 22 having a footstock center 23. The headstock center 2| and the footstock center 23 are arranged rotatably to support the opposite ends of a work piece I9 during a grinding operation. The headstock 28 is preferably electrically driven by means of an electric motor 24 which is mounted on the upper surface of the headstock and which is .connected by a V-belt drive (not shown) contained within a casing 25. The belt drive from the motor 24 serves to drivingly rotate a headstock spindle 21 which in turn supports the headstock center 2 I.

The work supporting table I6 is arranged to be traversed longitudinally relative to the base I5 to facilitate positioning the work piece, such as a crankshaft |9, in a predetermined position for a grinding operation. In the preferred construction, the motor driven traversing mechanism is provided, comprising a reversible electric motor which is mounted within the machine base I5 of the machine. The motor 38 is provided with an armature shaft 3| which supports a gear 32. The gear 32 meshes with a gear 33 which is mounted on the end of a rotatable shaft 34 which is journalled in bearings 35 and 36 formed in the casing 31. The shaft 34 has a worm 38 formed integral therewith-which meshes with a worm gear 39. The worm gear 39 has a central threaded aperture which meshes with or engages a stationary non-rotatable screw 48. The screw 40 is supported at its opposite ends by means of a pair of spaced depending brackets 4| and 42. The worm gear 39 is free to rotate on the screw 40 but is held against endwise movement by thrust bearings (not shown) formed within the casing 31. It will be readily apparent from the foregoing disclosure that when the motor 30 is started, a rotary motion is transmitted through the gear 32, the gear 33, the shaft 34, the Worm 38, to rotate the worm gear 39. The worm gear 39, being held against endwise movement relative to its supporting casing 31, produces an endwise movement of the screw 40 and transmits a corresponding endwise movement to the work supporting table I6. The motor 30 is a reversible type motor, consequently it can be rotated in either direction to produce a traversing movement of the table I6 either toward the left or toward the right, as desired.

Table locating mechanism The table I6 is preferably automatically adjusted to position successive work pieces in a desired and predetermined position relative to spaced portions thereon to be ground. An automatic table locating mechanism is provided, comprising a work engaging feeler arm which is positioned to engage a locating surface 46 on the crankshaft I9. The feeler arm 45 is mounted on the end of a slidably mounted rod 41 which is supported in bearings 48 and 49 in the headstock 20. A spring 50, surrounding the rod 41 and interposed between a collar 5I on the rod 41 and an inner surface of the headstock frame. serves normally to move the rod 41 and the feeler arm 45 toward the right (Fig. 2). The rod 41 carries a member 52 on its outer end which is provided with cam faces 53 and 54 which are arranged to engage and actuate electric switches 55 and 56 automatically to close a circuit to cause a rotation of the motor 38 in either direction. Unless the locating surface 46 on the crankshaft I9 is located in the position shown in Fig. 2, one or the other of the switches 55 or 56 will be moved downwardly by the cam faces 53 or 54, respectively, to close either the forward or reverse circuit to start the motor 38 and to move the table I6 longitudinally. As soon as the table has been adjusted longitudinally a sufficient amount so that the feeler 45 moves into the position shown in Fig. 2, the member 52 returns the cams 53 and 54 to allow the switches 55 and 56 to return to their uppermost position, thus breaking the circuit to stop the table traverse motor 30 and table I6 when the work piece is located in a predetermined position with respect to the operative faces of the grinding wheel. In order to facilitate setting up the machine for a given work piece, the member 52 is preferably adjustably mounted on the rod 41, such as by means of opposed nuts (Fig. 8). The switches 55 and 56 are also preferably supported by means of a bracket 51. The bracket 51 is adjustably supported on a bracket 58 which is xedly mounted relative to the headstock 28. An adjusting screw 59 is provided to facilitate transverse adjustment of the bracket 51. Clamping screws maintain the bracket 51 in fixed relation with the bracket 58. These clamping screws pass through elongated slots in the bracket 51 and are screw threaded into the bracket 58, thus serving to adjust the switches 55 and 56 transversely relative to their respective cam bases 53 and 54.

Work drive The crankshaft I 9 is loaded automatically into the machine in a manner to be hereinafter described, and is moved endwise into operative supporting engagement with the headstock center 2|. A yieldably mounted driving pin 60 is supported on a pivotally mounted member 6I which is pivoted on a stud 62 carried by a face plate 63. The face plate 63 is supported on and rotated by the spindle 21. The pin 6| is arranged to engage a hole or aperture 64 in the end of the work piece and is normally held in driving engagement therewith by means of a spring 65. When the crankshaft I9 is placed in the machine and moved into supporting engagement with the center 2|, the pin 60 engages the end face of the crankshaft unless it is aligned with the locating hole or aperture 64. If the pin engages the end face of the Work piece, the pin together with the pivotally mounted member 6I rocks in a counterclockwise direction (Fig. 8) and a stud 66 carried thereby engages the face of a ring-shaped member 61 and moves it toward the left (Fig. 8). The ring-shaped member 61 is carried by a bracket 68 which is supported on a 1ongitudinally slidable rod 69 which is journalled in bearings 10 (only one of which has been shown in Fig. 8). The rod 69 is normally held in its right-hand position (Fig. 8) by means of a compression spring 1I which exerts a pressure on a bracket 12 which is xedly pinned to the rod 69. The bracket 12 carries an adjustably positioned screw 13 which serves when moved toward the left (Fig. 8) to actuate a limit switch 14. The

limit switch 'I4 is connected in a manner to be hereinafter described, so that when the work piece I9 is placed in operative position on the headstock center 2|the headstock motor 24 is started at a slow rate of `speed until the driving pin 60 slides into engagement with the aperture in the end of the shaft I9, after which the speed of the motor is automatically increased or `.stepped up to a desired and predetermined work speed for a grinding operation.

Footstoclc The footstock 22 is provided with a longitudinally movable spindle 'I5 which is provided at its outer end with a tapered aperture to receive the footstock center 23 `so as to support the right-handend of Vthe crankshaft I9. The footstock spindle I5 is preferably moved to and from an operative position'by means of a fluid pressure mechanism comprising a cylinder 'I6 having a piston 'I'I slidably mounted therein. A spring 'I8 interposed between the piston 'Il and the footstock spindle 'I5 is arranged yieldably to maintain the footstock center 23 in operative engagement with the work piece I9 during the grinding operation.- Fluid may be admitted through a pipe I9 into a cylinder chamber 80 to cause the piston 'I1 and the spindle 'I5 together with the footstock center 23 to move toward the left (Fig. 2)` into an operative position, or if desired fiuid under pressure may be admitted through a pipe 8|, into a cylinder chamber 82, to cause the piston 'II and footstock center 23 to move to an inoperative position.

The admission of fluid under pressure to the footstock cylinder I6 is preferably controlled by means of a control valve 83 which is preferably a piston type ycontrolvalve which is actuated by means of a solenoid l84. The solenoid 84 is electrical-ly connected to be actuated in timed relation with the movements of the other parts of the machine, in a manner to be hereinafter described.

An electrical interlock is provided, including a normally open limit switch 85 which is actuated by a pivotally mounted lever 86 supported on the footstock 22. The lever 85 lis actuated to close the switch 85 when the piston 'II is moved into an operative position with the center 23 engaging and supporting the work piece I9. The switch 85 is operatively connected to start the work drive motor 24 to rotate the headstock spindle 2l and the driving pin 60 carried thereby at a slow rate of speed until the driving pin engages the locating and driving hole in the end of the work piece I9, after which the Work drive motor 24 is speeded up to rotate the work piece I9 at the normal predetermined grinding speed.

Wheel slide In the grinding of long cylindrical type work pieces, such as spaced bearings on an automobile crankshaft, it is desirable to provide a plurality of spaced wheel slides in order that the machine may function more efficiently, thus eliminating the necessity of traversing the work table to position successive portions of the work relative to the grinding wheel. In the preferred construction, it is desirable to provi-de a grinding Wheel assembly comprising a. pair of spaced grinding wheel slides 90 and 9| which. support rotatable wheel spindles 92 and 93. respectively. The wheel spindle 92 supports a pair of spaced grinding wheels 94 and 95. The wheel spindle 93 supports three spaced grinding wheels 99, 9'!

and v98 which are arranged' to simultaneously grind the main bearings and'adjacent `portions at the opposite ends of the crankshaft I9. `Th`e wheel spindles 92` and 93 are preferably motor driven by means of electric motors |00 and I0I,` respectively, which are supported on the upper surface of the grinding wheel slides 90 and "9|, respective1y.` Multiple V-belt drives are provided within the casings |02 and |03, respectively,.forf drivingly connecting themotors |00 and IOI, respectively, with the wheel spindles 92 and; 93,- respecti-vely, to impart a rotary motion to the wheels 94, 95, 96, 91 and 98.

W heel feeding mechanism A fluid pressure wheel feeding mechanism is provided to control the feeding movement `and adjustment of the grinding wheel toward `and from the work support.` Independent feed controlling mechanisms are provided for each of the wheel slides 90 and 9|, respectively, so that each wheel slide may be fed independent of the other. If desired, the two controlling mechanisms are arranged so that each of the grinding wheels and their supporting slides may be fed simultaneously into grinding contact with the work to be ground. The Wheel slide 99 is provided with a depending half nut 83 which is diagrammatically shown as projecting from the side of the wheel slide (Fig. 2) and which mesheswith a rotatable feed screw 89. The rotatable feed screw 89 is rotatably supported in bearings (not shown) in the base I5. The feed screw 89 may be rotated manually for adjusting the wheel slide .90 in setting up the machine by a manually operable feeding mechanism to be hereinafter described.`

In order that the wheel slide 90 may berapidly moved toward the work piece to grind the same by the yplunge-cut method, the feed screw 89 is connected to a piston rod |04. A fluid preswith the piston rod |04.

A fluid pressure system is provided for conveying fluid under pressure to operate the wheel l feeding mechanism as wellas the other mecha-vr nisms of the machine which will be hereinafter.;

described. A motor driven fluid pressure pump- I 01 is arranged to pump iiuid through a pipe |08 from a reservoir |09 preferably formed within. the base I0,` and to force fluid through a pipe III] to a feed control valve I II which is arranged to control the` admission to and exhaust of fluid from the cylinder |05. A pressure relief valve ||2 is connected in the pipe line IIO andserves to maintain the desired pressure within the operating system `by allowing excess fluid under pressure to by-pass into the reservoir |09. The feed control valve I I I is a piston type valve comprising a valve stem I I3 having formed integrally therewith valve pistons I I 4, II5, II'G and II'I.

' In the position of the valve illustrated in Fig. 2,

fluid under pressure enters the valve chamber 4located between'the valve pistons II5 and III` A spring `|23 normally serves to maintain thelvalve stem |I3 in the position illustrated in Fig.:

2. A solenoid |24 is provided to shift the valve stem ||3 upwardly (Fig. 2) to reverse the direction of flow of fluid to and from the feed cylinder |05. This solenoid |24 is interconnected with the other mechanisms of the machine so that it is energized in timed relation with the remainder of the grinding cycle automatically to feed the grinding wheels and their supporting slides toward the work piece at the desired time.

Similarly, the wheel slide 9| is provided with a dependinghalf nut |25 which meshes with or engages a rotatable cross feed screw |26 which is in turn journalled in suitable bearings (not shown) in the base I5. The screw |26 may be rotated manually in the usual and well known manner to adjust the position of the wheels 96, 91 and 98, as desired. In the preferred form, however, a fluid pressure feeding and positioning mechanism is provided, comprising a uid pressure cylinder |21 which is flxedly mounted on the base I5 of the machine. The cylinder |21 contains a slidably mounted piston |28 which is connected by means of a piston rod |29 with the feed screw |26, so that an endwise movement of the piston |28 and piston rod |29 will transmit a transverse movement to the wheel slide 9| and the grinding wheel supported thereby.

A motor driven uid pressure lamp |30 is mounted in the base of the machine and is arranged to pump fluid through a pipe I3I from the reservoir |09 and to force fluid under pressure through a pipe |32. An adjustable pressure relief valve |33 is connected in the pipe line |32 to facilitate maintaining the desired operating pressure within the system. Fluid under pressure passing through the pipe |32 is conveyed to a feed control valve |34 which is preferably a piston type control valve comprising a valve stem |35 having formed integrally therewith a plurality of valve pistons |35, |36, |31 and |36. A spring |39 normally holds the valve in the position illustrated in Fig. 2. An electric solenoid |40 is provided and is connected to be actuated automatically in timed relation with the cycle of the machine to shift the feed control valve |34 into its reverse position. Fluid under pressure passing through the pipe |32 enters a valve chamber located between the valve pistons |36 and |31 and passes through apipe or passage |4| into a cylinder chamber |42 to cause a rearward movement of the piston |28 to move the wheel slide 9| and the grinding wheels 96, 91 and 98 supported thereby to an inoperative position. During this rearward movement of the slide, fluid within a cylinder chamber |43 is exhausted through a pipe or passage |44 which enters a valve chamber located between the valve pistons |35 and |36 and passes out through an exhaust pipe |45 which returns the exhaust fluid to the reservoir |09 within the base I5.

Dash pot The pistons and cylinders for feeding the grinding wheels above described produce a rapid approaching or receding movement of the wheel slides 90 and 9| to quickly position the grinding wheels for a grinding operation and to remove them to an inoperative position after a grinding operation has been completed. In order to slow down the approaching movement of the grinding wheels to a slow but uniform feeding movement.'

a dash pot feed controlling mechanism |46 and |41 is 'provided adjacent to the rear ends of the cylinders |05 and |21, which serves to reduce the rapid approaching movement of the wheels to a relatively slow infeeding movement which continues until a positive stop prevents further advance of the wheel and allows the wheels to grind out or finish grind the work. The dash pot feed controlling mechanisms |46 and |41 have not been illustrated and described in detail in the present application, since these are not considered to be part of the present invention. These mechanisms are identical with that shown in the prior U. S. patent to Wood and Flygare No. 2,151,669, above referred to, to which reference may be had for details of disclosure not contained herein.

Steadyrests In order to accurately grind the spaced portions of the crankshaft I9, it is essential to support the center of the shaft against defiection due to pressures of the grinding wheels. A pair of spaced steadyrests |50 and I5| are provided to engage spaced portions on the work piece I9. The steadyrests |50 and I5| are identical in construction, consequently only one of these steadyrests has been illustrated in detail (Fig. 5). Each of the steadyrests is provided with a pair c of work steadying shoes |52 and |53. The shoe |52 is carried by a horizontally movable member |54 which is adjustable toward and from the axis of the work piece I9 by means of a screw |55. Similarly, the lower steadyrest shoe |53 is supported on the end of a slidably mounted member |56 which is arranged for adjustment by means of an adjusting screw |51. Lock nuts |58 and |59, respectively, are provided to lock the screws and |51 in adjusted position. An adjustably positioned screw |60 and nut |6| are provided to support the steadyrest shoe |53 at a point directly below the work axis. Each of the steadyrests |50 and I5I is provided with an under dovetailed shaped surface |62 which mates with a correspondingly shaped surface |63 on a transversely movable slide |64.

In order to load work pieces into alignment with the work centers, it is preferable to employ the work steadyrests for conveying the work piece from a loading position into alignment with the headstock and footstock centers. The steadyrest supporting slide |64 is, therefore, provided for movement in a transverse direction. The member |64 is provided with a dovetailed slideway |65 which mates with a dovetailed surface on the upper face of a longitudinally movable slide |66. The member |66 is provided on its under surface with a dovetailed slideway |61 which mates with a correspondingly shaped dovetailed surface |68 (Fig. 5) formed on the upper surface of the work table I6, thus providing a structure in which the two steadyrests |50 and |5| may be moved simultaneously in a transverse direction, that is, normal to the work axis to position a work piece in operative position within the machine, or may be moved longitudinally in a direction parallel to the work axis to complete the loading operation by positioning the work piece in operative engagement with the headstock center and the headstock driving pin.

The transversely movable slide |64 is provided with a depending rack bar |69 which meshes with a gear |10. The gear |10 is supported on one end ofa rotatable shaft |1| which is journalled in suitable bearings |12 and |13 which are fixedly mounted on the upper surface of the table I6. To facilitate a transverse positioning movement of the steadyrests |50 and |5| together v with their supporting slide |64, a fluid motor |15 is provided for rotating the shaft |1I. The mo- 2,276,206 'tor |15 is preferably a single vane type motor to transmit a transverse movement through the rack bar |69 to move the slide |64 and the steadyrests |50 and I5| to an inoperative or Vloading position. During this movement fluid -of the vane |16 to cause a transverse movement of the slide |64 and the steadyrests |50 and I5| toward the grinding wheels to position a crankshaft into alignment with the headstock center 2| and footstock center 23. Fluid under pressure is conveyed from the pump |01, through the pipe ||0, and through a pipe |85 to a control valve |86. The control valve |86 is preferably a solenoid operated valve having an electric solenoid |81 to open and close the valve ports. In the position illustrated in Fig. 2, uid entering the valve |86 passes out through the pipe |82, into the motor chamber |8I, to cause a clockwise movement of the vane |16 (Fig. 7). DuringA this movement fluid under pressure within the charnber |80 exhausts `through pipe |19, through a control valve |88 which is actuated by a solenoid |89, and passes out through a pipe |90 into the exhaust pipe |45 which returns the fluid to the reservoir |09. The solenoids |81 and |89 are electrically connected with the other mechanisms of the machine so that the fluid motor |15 is operated in timed relation with the `other parts of the machine to produce a desired operating cycle.

A mechanical latch device (Fig..5) is provided tov limit the forward movement of thev slide |64v carrying the steadyrests |50 and |5I in a position aligned for loading a shaft I9 into the machine. This latching device comprises a fixed stop abutment |92 which is formed integral with or xedly mounted on the end face of the transverse slide |64. The abutment |92 is arranged to engagea spring-pressed latch pin |93 when the slide |64 moves toward a loading position automatically to position the steadyrest shoes |52 and |53 to receive the shaft I9 when a loading arm 200 is swung into an operative position. The latch pin I 93 projects from the upper end of a springpressed plunger |94 which is normally held in an` upward position by means of a compression spring |95. The top of the latch pin |93 is angled off on its right-hand side face so that when the slide |64 moves toward the left (Fig. 5), the abutment |92 will force the latch pin |93 downwardly to `allow the slide |64 to move to its extreme rearward position.

' On the forward movement of the slide |64, the abutment |92 engages the left-hand end face of the latch pin |93 positively to stop the forward movement of the slide |64. The arm 200 then swings downwardly into a horizontal position to place the crankshaft I9 in position on the steadyrest shoes |52 and |53, respectively. During the downward movement of the loader arm 200, the arm 200 engages an upwardly projecting pin |96 which is moved-downwardly as the loader arm approaches a horizontal position to trip the latch pin 93 and thereby allow the slide |64 to continue its forward movement to transfer the unground shaft |9 into operative position in 'alignment with the work supporting centers 2| and 23, respectively.

Work loading and unloading `ouoparatus To facilitate maximum production from the machine, an automatically actuated work loading and unloading apparatus is provided for removing a finish ground shaft from the steadyrest when in a rearward position and to place an un- Vground shaft on said steadyrest when the slide |64 is moved transversely toward an operative position.

A work loading device has been provided comprising the pivotally mounted work loader arm 200 which is pivotally supported on a stud 20|. The stud 20| is supported in bearings 202 and 203 formed in upwardly extending arms 204 and 205 formed integral with a bracket 206 which is rigidly fastened to the frame of the footstock 22. A crankshaft I9 is loaded into a substantially U-shaped clip 201 formed in the end of the loader 200. The loader arm 200 is normally held in a vertical position, in which position the crankshaft I9 is loaded therein.

A suitable actuating mechanism is provided automatically to swing the loader arm 200 from its normal vertical position into a horizontal position, such as that'shown in Figs. 9 and 10, to place the unground crankshaft I9 in supporting engagement with the shoes of the steadyrests |50 and I5I. In the preferred construction, a fluidpressure mechanism is provided comprising a fluid pressure cylinder 208 having a piston 209 sliclably mounted therein. 'The piston 209 is connectedl to one end of a piston rod 2|0 which carries a rackrbar 2II -at its outer end. The rack bar 2II meshes with a gear segment 2I2 which is supported on the stud 20| and flxedly mounted relative to the arm 200. When vfiuid under pressure is admitted through a pipe 2|3 (Fig. 9) into la cylinder chamber formed at the right-hand end ofthe cylinder 208, the piston 209, the piston rod 2I0, and the rack bar 2|I are moved toward the left (Fig. 9) which serves to rotate the gear segment to raise the loading arm 200 into its normally vertical position. Similarly, when fluid under pressure is admitted through a pipe 2I4 into the cylinder chamber formed at the lefthand end of the cylinder 208, the piston 209, the

piston rod 2|0, and 'therack bar 2II transmit a rotary movement to the gear segments 2|2 to swing the loader arm from its normally vertical position to the full line position shown in Fig. 9 to position a crankshaft to be ground in supporting engagement with the steadyrest shoes on the steadyrests |50 and I5I. An arcuate shaped plate 2I5 is fixedly mounted on the footstock 22 and serves to cover the open side of the U-shaped Vclip 201 during the swinging movement ofthe arm 20-0 until it reaches its lower or horizontal position so as to aid in maintaining the shaft I9 in position during the loading operation.

l A solenoid actuated latch |91 is normally held in the path of movement of the work loader arm 200 by means of a tension spring |98. A solenoid |99 is energized when the steadyrest cross slide I 64 moves forward to a predetermined loading position to withdraw the latch |91 against the tension of the spring |98. The energization of the solenoid I 99 is-control1ed by a limit switch `which is actuatedby the transverse movement 'of the cross slide |64.

ajbase plate or framev226. .xedly mounted on a. projecting base plateof the .footstock 22. The unloading arm 220 is provided `With a substantially U-shaped clip 221 which is .adapted to support the end of a ground crankshaft as -the shaft is moved to an inoperative position by means of the transverse movement A similar unloadingnor discharge mechanism is provided comprising an unloader arm 220 which is pivotally supported on a stud 22| which is supported in bearing members 222 and 223. The bearing members 222 and 223 are supported in arms 224 and 225 which are formed integral with The frame 226 is of the steadyrest |50 and |5| (above described).

AAn actuatingmechanism is provided, comprising a fluid pressure cylinderk 228 having a piston 229 slidably mounted therein. The piston 229 is connected to one end of a piston rod 230 having a rack bar 23| formed integral with its outer end. The rack bar 23| meshes with a gear segment 232 which is supported on the stud 22 .and is xedly mounted to move the unloader arm 220. When uid under pressure is admitted through the pipe 233 into a cylinder chamber 234 `formed at the right-hand end of the cylinder 228 (Fig. 9), it causes a movement of the piston ,229, the piston rod 230, and the rack bar 23| toward the left to rock the gear segment 232 and .swing the unloader arm 220 from a horizontal to a vertical position so as to remove a ground crankshaft from position on the steadyrest. Similarly, when fluid under pressure is admitted through a pipe 235 into a cylinder chamber 236 formed at the left-hand end of the cylinder 228, the piston 229, the piston rod 230, and the rack ,bar 23| are moved toward the right into the position illustrating in Fig. 9 to rock the gear segment 232 and to swing the unloading arm 220 from a vertical into a horizontal position, as- 4shown in Fig. 9.

i toward a vertical position automatically to move the ground crankshaft I9 out of engagement with the steadyrest and into a position where it may l be readily removed from the machine in a manner to be hereinafter described.

A control valve 240 is actuated by means of a solenoid 24| and serves to control the admission to and exhaust of fluid from the cylinder 208. Fluid under pressure from the pump |30 passes through the pipe |32 and through a pipe 242 into the valve 240 which is preferably a piston type valve. In the position of the valve (Fig. 2), fluid under pressure passes from the valve 240, through a pipe 243, into a cylinder chamber located at the right-hand end of the cylinder 208 (Fig. 2) to move the piston 29 toward the left to swing the work loading arm 200 into its normal or vertical position. The energization of the solenoid 24| is preferably controlled automatically in timed relation with the other mechanisms of the machine, so that the work loader is swung downwardly at the proper time in the cycle of operation. When the solenoid 24| is deenerf, various machines.

laerdzoc gized to allow the valve 240 to move downwardly (Fig. 2), luid under pressure from the pipe 242 passes' through a pipe 244 into -a cylinder chamlber at the left-hand end of the cylinder 208 to move the piston 209 toward the right and to transmit a corresponding movement to the rack bar 2|| to swing the work loader arm 200 from a vertical toward a horizontal position.

A control valve 245 which is actuated by means of a solenoid 246 is provided to control the admission of fluid to and the exhaust of uid from the cylinder 228. Fluid under pressure from the pipe |32 passes through a pipe 241 and in the position illustrated in Fig. 2, passes out through a pipe 248 into the cylinder chamber at the righthand end of the cylinder 228 (Fig. 2) to move the piston 229 and rack bar 23| toward the left so as to swing the work unloading arm 220 into its vertical position. Similarly, when the solenoid 246 is deenergized, iiuid under pressure from the valve 245 passes through a pipe 249 into a cylinder chamber at the left-hand end of the cylinder 228 to move the piston 229 and the rack bar 23| `toward the right (Fig. 2) to swing the work unloading arm 220 in a counterclockwise direction from a vertical toward a horizontal position so as to align the U-shaped clip 221 (Fig. 10) in position to receive the end of the ground crankshaft |9 when it is moved transversely from the work supporting center.

Work conveyor In the large automotive plants, endless conveyors are provided to convey work pieces to the The work pieces are then removed from the conveyor manually and placed in the machine for a grinding operation, after which they are removed from and again placed on the conveyor to be conveyed to other machines for different operations. The lifting of heavy work pieces from the conveyor into the machine and vice versa is fatiguing upon the operator; consequently to attain one object of the invention, a manually controlled mechanical transferring mechanism is provided for transferring an unground work piece into the work loading device and returning it to the conveyor after a grinding operation has been completed. An `endless conveyor track 260 (Fig. 1) is provided with and endless conveyor comprising Ia plurality of roller-supported Work carrier members 26|, 262 and 263 which are interconnected by links 264, 4265. The carrier members 26|, 262 and 263 serve to support a plurality of crankshafts |9 in a position adjacent to the grinding machine.

A work transfer member 266 is provided with a yoke-shaped end 261 which is arranged to engage and remove a crankshaft |9 from one of the work carriers 26|, 262 or 263. The transfer member 266 is supported on a pivotally mounted frame 268 which is in turn supported by means of a vertically arranged stud 269 on the end of a lift arm 210. The arm 210 is xedly supported at the upper end of a vertically movable fluid pressure cylinder 21|. A piston 212 is slidably mounted within the cylinder 21| and is connected through the upper end of a hollow piston rod 213, 'the lower end of which is anchored `to the base of the machine. The cylinder 21| is arranged to slide vertically in a central aperture formed within the column 214. A motor driven fluid pressurepump 215 within the base l5 of the machine conveys fluid from a reservoir 216 through a pipe 211 to a solenoid actuated control valve 218 which serves. to admit fluid under pressure through a pipe 219, the hollow piston rod 213, into a cylinder chamber 288 formed above the piston 212 to move the cylinder 21| together with the arm 218 and the work transfer mechanism supported thereby in a vertical direction. During this movement, fluid within a cylinder chamber 280m located below the piston 212 is exhausted through a pipe 282 into the reservoir 216,

The solenoid actuated control valve 218 is a piston type valve (Fig. 3) comprising a valve stem 28| having formed integrally therewith a plurality of spaced valve pistons. A pair of balanced springs 283 normally serve to hold the valve 218 in a central or neutral position so that fluid is held within the cylinder chambers on both sides of thepiston 212 to hold the work transfer stationary. A solenoid 284 serves when energized to move the valve stem 28| toward the right (Fig. 3) to pass fluid under pressure through the pipe 219 to raise the work transfer arm 218 when desired. A solenoid 285 serves when energized to move the valve stem 28| toward the left (Fig. 3) to pass fluid under pressure through the` pipe 282 to lower the work transfer arm 218 when desired.

A manually operable control device is provided to facilitate both a swinging and lifting movement of the transfer member 266. A manually operable handle 286 is supported at the lower end of a vertically movable rod 281. The rod 281 is slidably supported in a bracket 288 which is carried by the transfer member 286. A block 289 is xedly mounted on the upper end of the rod 281, and a block 298 is fixedly mounted on the lower end of the rod and serves to support the handle 286. A pair of balanced compression springs 29| and 292 serve to normally hold the handle 288 together with the rod 281 and the blocks 289 and 298 in the position illustrated in Fig. 3.` An upward movement of the handle 288 serves to close a normally open switch 293 which is connected to energize the solenoid 284 to shift the valve stem 28| toward the right (Fig. 3) to admit fluid under pressure into the cylinder chamber 288 to cause an upward vertical movement of the cylinder 21| and the arm 218 together with the transfer member 266. Similarly, a downward movement ofthe handle 28 serves to close a normally open limit switch 294 which in turn serves to energize the solenoid 285 to shift the valve stem 28| toward the left (Fig. 3) to admit fluid under pressure into the lower cylinder chamber 288a to cause a downward movement ofthe cylinder 21|, the arm 218, andthe work transfer member 266. By bodily moving the handle 288 inV a transverse direction, the arm 218 together with the cylinder 21| may be rotated about the axis of the cylinder as a pivot and the pivotally mounted frame 268 which supports the work transfer member 266 may be swung about the pivot 269.

It will be readily apparent from the foregoing disclosure that the operator, by manipulation of the handle 286, may raise the work transfer member 266 and at the same time swing it in a horizontal plane into position to grip a crankshaft supported on the work carrier of the endless conveyor and to swing it downwardly and laterally to transfer the unground work piece into position so that its lower end is supported by the substantially U-shaped clip 281 on the work loading arm 288. The handle 285 may then be moved to withdraw the work transfer member 266 and to swing it so that its yokeshaped member 261 engages a ground shaft just removed from the machine whichv is supported in the U-shaped clip 221 formed in the end of the unloading arm 228. The handle 285 may then be manipulated to raise the cylinder 21| and swing the work transfer member 266 to again position the ground crankshaft on a vacant work carrier on the endless conveyor, by means of which the shaft is conveyed to other parts of the factory. An auxiliary handle 295 is provided on the work transfer member 286 to enable the operator to use both hands, if desired, the handle 295 serving to produce a transverse movement of the work transf-er member 286, and the handle 286 serving to control the up and down movement thereof in the manner above described. It will be readily apparent, there-.- fore, that either one or both hands may be employed to readily swing the crankshaft from the endless conveyor into position on the loading arm and to remove the ground shaft from the unloading arm and readily transfer it again to the endless conveyor overhead without undue fatigue on the part of the operator.

The operation of the improved crankshaft grinding machine will be readily apparent from the foregoing disclosure. Assuming all of the parts to have been previously adjusted and a crankshaft has been placed in operative supporting engagement with the headstock center 2| and footstock center 23 and a grinding operation thereon has been completed, as soon as a grinding operation has been completed 0n a crankshaft |9, the push button switches 388 and 30| are actuated to break a circuit to deenergize the magnetic switches 382 and 383, respectively. The opening of the magnetic switches 382 and 383 serves to open magnetic switches 384 and 385, respectively, to deenergize the solenoids |24 and |48, respectively. The deenergizing of the solenoids |24 and |48 serves to release the compression of the springs |23 and |39, respectively, to shift the control valves and |34, respectively, into the positions illustrated in Fig. 2 so as to admit fluid under pressure to move the pistons |86 and |28, respectively, in a rearward direction to remove the wheel slides 98 and 9| together with their respectivevgrinding wheels 94, 95, 96, 91 and 98 t a rearward or inoperative position.

When the wheel slides 98 and 9| reach their rearward position, the limit switches 386 and 381 are automatically closed which servesto close circuits to energize the magnetic switches 389 and 3|0. The energization of the switch 3|8 serves to energize the solenoid 84 to move the footstock control valve 83 in an-upward direction (Fig. 2) to admit fluid under pressure through the pipe 8| to the footstock cylinder chamber 82 to cause the piston 11 together with the spindle 15 and footstock center 23 to move toward the right (Fig. 2). This movement of the footstock to `an inoperative position serves through the lever 86 to open the limit switch 85 which in turn stops the work drive motor 24. As the footstock piston 11 continues its movement toward an inoperative position, a lug 3|| carried by an extension of the piston rod serves instantaneously to actuate a switch 3|2` to again energize the. magnetic switches 382 and 383, respectively. This, however, has no effect on the mechanisms of the machine until the limit switch 85 is again to an inoperative position, a lug 3|3 which is nx- )edly mounted on the footstock spindle 15 engages a lug 3|4 projecting upwardly from the steadyrest supporting slide |64 to move the steadyrests |50 and I5| together with the slide |66 longitudinally toward the right (Fig. 2). This longitudinal movement of the steadyrests |50 and |5| moves the ground crankshaft I9 toward the right to withdraw it from engagement with the headstock center 2| and from engagement with the work drive pin 60 so that the ground crankshaft is supported on the steadyrest shoes |52 and |53 of the steadyrests |50 and |5| and the headstock end of the shaft I9 rests on a supporting bracket3|5 the upper surface of which is shaped to engage and support the shaft during the first part of the unloading operation.

When the footstock center 23 reaches its righthand or inoperative position (Fig. 2), a normally open limit switch 322 is closed, which serves to close a circuit to energize the solenoid 246 t shift the valve 245 upward. The shifting of the .valve 245 admits fluid under pressure through the pipe 249 into the cylinder chamber at the left of the piston 229 to swing the unloader arm 220 in a counterclockwise direction into a horizontal position to receive the ground crankshaft I9. During the downward movement of the unloader arm 220, a lug carried by the arm 220 actuates a switch 3|1 which serves to energize the solenoid |89 to shift the control valve |88 so as to admit uid under pressure through the pipe |19 into the uid motor chamber |80 of the fluid motor to effect a rearward transverse movement of the steadyrest supporting slide |64. This movement of the slide |64 conveys a ground crankshaft I9 from a position in alignment with the headstock center 2| and footstock center 23 into a position where the end of the crankshaft engages the U-shaped clip 221 at the end of the unloader arm 220. The actuation of the switch 3|1 during the downward swinging movement of the unloader arm 220 serves to break a circuit to deenergize the solenoid |81 so that fluid exhausting from the fluid motor chamber |8| through the pipe |82 may exhaust out through the'pipe |45 into the fluid reservoir |09 within the base I5 of the machine.

As the transversely movable slide |64 carrying the steadyrests |59 and |5I, respectively, approaches its rearward or inoperative position, a lug 3|8 carried by the transverse slide |64 actuates a limit switch 3I9 to close a magnetic switch 320 which in turn closes a circuit to energize the solenoid 24| which shifts the loader control valve 240 in an upward direction (Fig. 2) to admit fluid under pressure through the pipe 244 into a cylinder chamber at the left-hand end of the piston 209 (Fig. 2) to move the piston 209 toward the right. This movement, through the rack bar 2|| and the gear segment 2I2, swings the loader arm 200 in a counterclockwise direction (Fig. 2) until an abutment on the loader arm 200 engages the solenoid actuated latch plunger |91. The loader arm 200 has been previously loaded with a new unground crankshaft and the latch |91 holds the loader arm 220 together with the unground crankshaft supported thereby in position just clearing the steadyrests |50 and 5|.

When the ground crankshaft I9 moves transversely into operative engagement with the clip 221 at the end of the loader arm 220, the shaft 245 to move into the position as shown in Fig. 2 to admit fluid under pressure through the pipe 248 to cause the unloader piston 229 to move toward the left so as to swing the unloader arm 229 together with the ground crankshaft to a vertical position. The swinging movement of the unloader arm 220 to a vertical position again actuates the switch 3| 1 so as to deenergize the solenoid |89 to shift the valve |88 into the position as shown in Fig. 2 and at the same time to energize the solenoid |81 so as to admit fluid under pressure through the valve |86 and the pipe |82 into the fluid motor chamber |8I to initiate a forward movement of the transversely movable slide |64. The forward movement of the slide |64 together with the steadyrests |50 and |5| continues until the stop abutment |92 formed on the slide |64 engages the mechanically actuated latch pin |93 positively to limit the forward moveme of the slide |64 in a loading position. At the same time the lug |92 stops the transverse movement of the slide |64, a limit switch 32| is closed to energize the solenoid |99 which serves to withdraw the latch |91 against the tension of the spring |98, thus releasing the loader arm 200 and allowing it to continue its movement in a counterclockwise direction (Fig. 2).

The unground crankshaft I9 is supported thereby in operative position in engagement with the steadyrest shoes |52 and |53 and also the bracket 3l5. As the loader arm swings into an operative position, the loader arm engages and moves downwardly the plunger |96 which serves to depress the mechanical latch pin |93 to move it out of the path of the stop lug |92, after which the fluid under pressure within the motor chamber I 8| may continue the forward transverse movement of the slide |64 to position the unground crankshaft in alignment with the headstock center 2| and the footstock center 23. When the transversely movable slide |64 carrying the steadyrests |50 and |5| together with the work piece I9 reaches the forward or operative position, a limit switch 326 is opened to deenergize the magnetic switch 3|!) which in turn opens a circuit to deenergize the solenoid 84, thus shifting the footstock control valve 83 into the position illustrated in Fig. 2 to admit fluid under pressure through the pipe 19 into the cylinder chamber to move the piston 11 together with the footstock spindle 15 and the center 23 toward the left (Fig. 2) into engagement with the footstock end of the crankshaft |9. The movement of the footstock continues and it in turn moves the crankshaft I9 together with the steadyrests |50 and I 5| together with the longitudinally movable slide |66 toward the left so as to move the headstock end of the crankshaft into operative engagement with the headstock center 2|. Movement of the footstock into an operative position closes the limit switch which serves to start the headstock motor at a slow speed.

When the driving pin 60 rotates so that it drops into the driving aperture 64 (Fig. 8) in. the end of the crankshaft, it closes the limit switch 14 which is connected in series with' the limit switches 55 and 56 of the table locating device 52. If both of the switches 55 and 56 are closed, as determined by the work feeler arm 45, the magnetic switch 309 is closed to start the work drive motor 24 at the normal grinding speed for the work. If the work piece is not in a lpredetermined aligned position, either the switch' 55 or 56 will be opened due to the moveapropos .ment .ofthe @am 53 or L54, respectively, andthe 'table positioning-mmm? 1'30 Will be iI'Otatdn Cine ithrough the magnetieswitohes 306iandf31 Awhich in turn serve to energize the wheel feedfsolenoid `|24 and |40, -respectively,-to ymove `the valves III and |34 upwardlyKFig. v2) Aso =a`sto admit fluid `under Apressure through `tifa-pipe 21| 4fand 144, respectively, lto causea -forward Jfeeding vmovement of the wheel sli-desf and'QI, respectively, to move the wheels 94595,196, `v8-1fandiii8 into operative Lgrinding Contact 'with' the portions of the work piece to be grou-nd.

Allimit switch -3'21 is --mounted :lon the larcuate guard plate 231 and is "arr-angedso that when the `unloaderlarm 22|) swings to avrltical position with acrankshaft supported therein, fthe fcrankshaft will open the switch "321 yandinaintainfthe circuit open fso that the solenoid-i266 'cannot-be energizedor the unloader put through its next cycle until the iinish 'ground crankshaft has been -removed therefrom. `The above c'y'cle of operation -is then continued to grind successive crankshafts.

Work pieces are conveyed from anfoverhea'd endless carrier `toftheloading arm by afmanually controlled. hydraulic mechanism, above -described, whichfis controlled bythe manuallyoperable handles v286 and 295, respectively.- The operator grasps the handle 286 (Fig. 1) Aand moves it upwardly whichcloses the switch-292 to -ac'tuate 'the solenoidlvZM to sh-ift the lvalve V218 Itoward the right (Fi-gt3) -soYas-tofadmit flu-id under pressure to the cylinder chamber I2-8l) to move the cylinder `21| together with 'the work conveying mechanism including armlZl upwardlyinto dotted line position `21|la. -At the same time, the 'Work carrier `head 3266 may -be 'ls'wung transversely into dotted 'line posi1tion-266a by movementof the handle 286 eitherutilized alone or in `comloination the handle esaurire yoked portion 261 Iis swungintoipositionwa( into engagement with a portionofthe crankshaft I9 which is supported Yon the `endless, conveyor, to lift `the shaft from the conveyor, iafter which the handle 28E is moved downwardly and "the carrier 266 swung in a substantially horizontal direction to swing the end -of the/crankshaft I9 into yalignment with "the substantially -U `sha`ped clip 201 on the loader -arm 200, Lthus lpl'acing a new unground work piece in `position on 'the loaderarmfor the next yloading operation. AThe device may then be swung 'in-to position so that the yoke 261 will engage andpickupithe ground shaft I9 in Ithe unloader -arm `2-21) `and by nipulation of th'e handle 286 tneground-shaft may be again reconveyed to the 'endless conveyor adjacent to the machine. A normally open limit switcheiill is opened when the loader arm 20e iis swung away/from i a vertical position to opena circuitand'thereby render the solenoid |89 inoperativeiexeept when the loader arm 200 is in a vertical position. A normally'closedliinitswitch 325 is opened when the-slide 4Hill supporting the steadyrests |50 and |5| is in the forward or operative position and serves asa safety switch to maintain the solenoid 24| deenergized to hold the loader arm 200 in a vertical position. A normally closed limit switch 1326 serves as fa safety device -to opeh'the switch 3 0 when -the Aisteafd-yrest Asupporting slide is fin a forward or operative position.

It will be `readily apparent' Ifrom#theforegoing disclosure thatithe llie'avy Lcrank'slfiaft may be `mech'anically conveyed-Tinto an operative positionedllinthe 'm-"achiifle and ground with-the `minimum attention on the part of the operator.

It will thus-be seen that there -lias be'en -provided by this invention apparatusin which Athe various `objects hereinabove set ffor'th together with lmanylthoroughly practical advantages *are successfully achieved. manypossible embodiments may be y-made of theabovelinvention "and as many changes might be made -in theleinbodimentl above isetforth-it is -t`o '-be understood that 'the accompanying drawings is to Abefinterpreted as illustrative and. not fin "a limitingsense. I We lclaim:

1. In -a grinding machine ha-ving =a basegafrotatable Lgrinding wheel, a transversely '-movable slide Ito support `said wheel,a longitudinally-movable tableya rotatable work support thereon including a headstock and a footstoek, lzn'eanst'o feed said Aslide transversely, meansfto traverse said table longitudinally, -means includingauid motor to actuate saidfootstock, "-a work loading device `pivotally 4lrnounted on said table `'lautornatically-to swing a work piece into operative position in alignment with the headstock and io'otstock, anda work transfer mechanism on said base rto trans-fer a work piece from Aa vwork-carrying conveyor to said Lwork loading device.

-2. plne; grinding machine `havinga base, a rotatable grinding wheel, :a transversely -movable slide to support sai'diwheelfa longitudinally mov- 'able table, arotatable Work support 'thereoniin'-` cluding-'a headstock and a footstock, means to feed said slide transversely, means to traverse said table longitudinally, Ameans including1a1uid motor v'to actuate :said 'footstocln ja `pivotally mounted "work loading device on "said tableautomatically to swing a work piece'into operative position Ain alignment with the he'adstock `and footstocln 'and a'hydraulically operated, electrically controlled worktransfer mechanismen said base to transfer a work piece fromla work car rying conveyor to said work loa'ding'devic'e.

3. InV a-grinding machine asclaiIned-inlaiml, the combination Vwith the parts 4and 'features thereinv specified 'in which the work `transfer mechanism on the `Work table-comprises a 'movably mounted work gripping member, meansincluding a piston andcylinder to move `said membervertically, 'means includinga solenoid actuated valveto convey'fluid underpressureto said cylinder, and means including a manually operable levercontrolled switch on said member to actuate said solenoid valve so asto raise orllower said member and also manually to Aswing said member to facilitate the transfer of 'a work piece from a `conveyor tothe grinding machine.

4. Ina grinding machine as claimed linclairnl, the combination with the parts -and features therein specified -in which the work transfer mechanism on the work-` table-compriseslialvertically movable, pivotally mounted lworkfgri'pfp'in-g member =and a manuallyoperable -coritrol lever which is arranged so that a vertical movement of the lever controls a power operated lift vertically to move said member and a horizontal movement of said lever serves manually to swing said member to position a work piece relative to a work loader on said machine.

5. In a grinding machine as claimed in claim 1, the combination with the parts and features therein specified in which the Work transfer mechanism on the work table comprises a pivotally mounted work gripping member, means including a piston and cylinder to move said member vertically, means including a solenoid actuated valve to convey fluid under pressure to said cylinder, and means including a manually operable lever controlled switch on said member to actuate said valve so as to raise or lower said member and also manually to swing said member to facilitate the transfer of a work piece from said conveyor to the grinding machine.

6. In a grinding machine having a longitudinally movable table, a headstock and a footstock on said table rotatably to support a work piece, means including a, yieldably positioned driving pin on said headstock to engage an aperture in the end of a work piece, means including a fluid motor to move said ootstock center to and from an operative position, a steadyrest which is supported on-said table, means to move said steadyrest simultaneously toward and from an operative position to convey a Work piece into position in alignment with said headstock and footstock, and means actuated by movement of said footstock center into an operative position longitudinally to move the steadyrest and work piece to position the Work piece in operative supporting engagement with said headstock center.

'7. In a grinding machine having a rotatable grinding wheel, a transversely movable slide to' support said wheel, a longitudinally movable table, a rotatable Work support thereon including a headstock and a lfootstock, means to feed said slide transversely, means to traverse said table longitudinally, a transversely movable steadyrest having work engaging shoes thereon, means including a fluid motor to move said steadyrest transversely, means including a fluid motor to move said footstock center toward and from an operative position, a movable work loading device to support a work piece to be ground, means including a fluid motor to move said Work loader to convey a work piece supported thereby onto said steadyrest shoe when the steadyrest is in an inoperative position.

8. In a grinding machine having a transversely movable rotatable grinding wheel and a longitudinally movable rotatable work support, means to feed said grinding wheel transversely, means to traverse said work support longitudinally to position a Work piece in operative relation with the grinding wheel, a transversely movable work steadying rest, means to move said steadyrest transversely to and from an operative position, a pivotally mounted work loader to support a work piece to be ground, and means to swing said work loader to convey a work piece supported thereby onto said steadyrest when the steadyrest is in an inoperative position.

9. In a grinding machine as claimed in claim 6, the combination with the parts and features therein specified, of a plurality of steadyrests to support and steady a work piece at spaced intervals between the headstock and footstock, a transversely movable slide to support said steadyrests, means including a iiuid motor to move said slide transversely to convey a work piece from an operative position in alignment with said headstock and footstock to an inoperative position, a hydraulically operated unloading device to remove a ground work piece from saidsteadyrests, a movably mounted loading device to convey an unground Work piece into an operative position on said steadyrests, means including a mechanical latch to limit the forward movement of thesteadyrest slide to maintain it in a loading position until a new work piece is in operative engagement with the steadyrests, and means actuated by movement of said loader arm to release said latch so that the transversely movable slide may continue its forward movement to convey an unground work piece into alignment with the headstock and footstock.

10. In apparatus as claimed in claim 6, the combination with the parts and features therein specified, of a fluid operated motor to move the steadyrest slide transversely, said steadyrest serving to carry a Work piece to and from an operative position, means including a pivotally mounted unloader arm which is arranged to receive a ground work piece when the steadyrest slide is moved to an inoperative position, means including a fluid motor to swing said unloader arm to an inoperative position to remove a ground work piece from the steadyrest, a pivotally mounted work loader arm which is arranged to swing an unground work piece into an operative position on said steadyrest when the steadyrest slide is moved toward an operating position to convey a new work piece into operative position in alignment with the headstock and footstock.

11. In a grinding machine having a rotatable grinding wheel, a transversely movable wheel slide therefor, a longitudinally movable table, a rotatable work support thereon including a headstock and a footstock rotatably to support a work piece, a pair of spaced steadyrests to support a work piece at spaced intervals between the headstock and footstock,V a transversely movable slide to support said steadyrest which is arranged to move the steadyrest to and from an operative position, said steadyrest serving to convey awork piece to and from an operative position in alignment with the work centers, a fluid motor to move said steadyrest slide to and from an operative position, and a pivotally mounted, iiuid pressure actuated unloader arm which is arranged to engage a ground work piece when the steadyrest slide is moved to an inoperative position, said loader arm being arranged automatically to remove the work piece from the steadyrest to an inoperative position.

12. In a grinding machine as claimed in claim 1l, the combination with the parts and features therein specified, of a fluid motor actuated rack and gear mechanism to move the slide and steadyrest transversely to and from an operative position, a pivotally mounted fluid pressure actuated unloader arm which is arranged to engage a ground work piece when the steadyrest slide is moved to an inoperative position, said unloader arm being arranged automatically to remove the work piece from supporting engagement with said steadyrest.

CARL G. FLYGARE.

JOHN I. GARSIDE. 

